Referring to FIGS. 1A and 1B, a conventional shielding device 10 is fixed on a printed circuit (PC) board by means of soldering. The shielding device 10 includes a frame body 11 and a connector 12 connected with the frame body 11 for signal output/input. In general, the connector 12 is fixed on the PC board through a soldering process, for example, by means of an infra-red (IR) reflow soldering oven. The IR reflow soldering oven is equipped with a heating unit having different temperature divisions for preheating/melting/condensing/cooling/solidifying the soldering paste, wherein the process temperature of the melting division ranges from about 230° C. to 265° C.
The connector 12 includes a metal sleeve 13 having a receiving hole 14 for receiving therein a first insulating member 15 and a second insulating member 16. A connection section 17 is disposed at a front end of the sleeve 13. The connection section 17 is inserted in a connection hole 18 of the frame body 11. The periphery of a juncture between the connection section 17 and a wall of the connection hole 18 is riveted and welded to integrally connect the connector 12 with the frame body 11. The connector 12 further includes a contact member 19 arranged in the first and second insulating members 15, 16. The contact member 19 has a rear end connected to a conductive wire of the PC board, whereby the contact member 19 is electrically connected with the PC board.
When the connector 12 is manually welded with the frame body 11, the welding hand tool is set to a high temperature of about 280° C. according to heat resistance of the components. However, the first insulating member 15 is made of nylon material, which has a heat resistance under about 200° C. As a result, after welded at high temperature, the first insulating member 15 will contract and deform and become freely rotatable within the sleeve 13.
Furthermore, the connector 12 is adhered to the PC board by means of IR reflow soldering oven. After welded at high temperature, the contact member 19 and the first insulating member 15 as well as the connection section 17 will deform and become freely rotatable relative to each other.
Accordingly, in a high-temperature operation environment, the first insulating member 15 is likely to deform and become freely rotatable within the sleeve 13. Also, the contact member 19 will become freely rotatable relative to the first insulating member 15. This is because the connector 12 has no anti-rotation structure.